CN112955348A

CN112955348A - Vehicle inductive charging with secondary side voltage measurement and secondary side to primary side reaction

Info

Publication number: CN112955348A
Application number: CN201980043150.1A
Authority: CN
Inventors: 马丁·埃勒尔; 马克·昂塞尔曼; 卢卡斯·伯赫勒; 马克·博施
Original assignee: Brusa Elektronik AG
Current assignee: Brusa Elektronik AG
Priority date: 2018-06-29
Filing date: 2019-06-24
Publication date: 2021-06-11
Anticipated expiration: 2039-06-24
Also published as: US12071032B2; DE112019003301A5; WO2020002227A1; US20210268920A1

Abstract

A secondary loop device, having: a secondary coil (L2) for transmitting and/or receiving magnetic energy of the magnetic field (106) and for converting the magnetic energy into electrical energy; an energy transfer device (405) for transferring electrical energy; secondary side detection means (409, 407); and a terminal switching device (301), wherein the magnetic field (106) is generated by a primary coil (L1) of the primary circuit arrangement (105'), the energy transfer device (405) has an input for coupling to a secondary coil (L2), the energy transfer device (405) has an output for providing electrical energy as a voltage and/or current, the secondary-side detection device (409, 407) is connected to the input and/or output of the energy transfer device, in order to detect an excess pressure at the input and/or output of the energy transmission device, and secondary-side detection devices (409, 407) are provided, influencing the magnetic field (106) in the secondary coil (L2) by means of the terminal switching device (301) when an overpressure at the input and/or output of the energy transmission device (405) is detected, so that a current jump and/or a voltage jump is caused in the primary coil (L1).

Description

Vehicle inductive charging with secondary side voltage measurement and secondary side to primary side reaction

Technical Field

The invention relates to the technical field of inductive charging. In particular, the invention relates to a secondary circuit arrangement, a primary circuit arrangement, a system for energy transfer, a method for testing a secondary circuit arrangement, a method for testing a primary circuit arrangement.

Background

In order to electrically charge an Electric Vehicle (EV) or a Hybrid Vehicle (PHEV) that operates with a combination of propellant and Electric energy, a system for inductive energy transfer may be used when the charging should be performed in a contactless manner. In such a system, a magnetic alternating field is generated in the frequency range of 25.. 150 kHz. It must be noted here that the limit value for the electromagnetic wave emission can be confirmed by international valid standards outside this frequency band. Since, although in principle, magnetic fields are used for energy transfer, electromagnetic waves are inherently involved on the basis of the fact that the magnetic field changes. However, since the field intensity changes slowly, the electromagnetic wave used in the induction charging has a wavelength of several kilometers.

In order to comply with the limit values for emissions, it is noted that the magnetic alternating field for energy transfer operates with fundamental oscillations in the 25.. 150kHz range and contains only very small higher harmonics. It is therefore possible to use filters which remove as far as possible the interfering higher harmonics. Furthermore, it must be taken care that, in order to comply with internationally valid standards and guidelines, the energy transfer is only carried out when a certain quality of coupling with respect to each other is achieved by adjusting a certain orientation of the coupling elements with respect to each other, for example by means of a positioning system as described in document EP 3103674 a 1.

Document EP 2868516 a1 describes a method for regulating the energy transferred for contactless energy transfer between two resonators of a system.

As coupling elements for energy transfer, a GPM (ground mat module) with a primary coil is used on the stationary side and a CPM (vehicle mat module) with a secondary coil is used on the vehicle side. The GPM and CPM form a transformer for coupling and energy transfer. The physical orientation of the coupling elements relative to each other is measured and adjusted by means of a positioning signal, such as an RKS (Remote Keyless Entry System). Different transfer paths and different transfer techniques may be used for energy transfer and for transfer of positioning signals.

However, the energy transfer may be disturbed due to load losses at the secondary side.

The task of the invention can be seen as enabling an efficient transfer of energy.

Disclosure of Invention

Accordingly, a secondary circuit arrangement, a primary circuit arrangement, a system for energy transfer, a method for testing a secondary circuit arrangement, and a method for testing a primary circuit arrangement are provided.

The subject matter of the invention is given by the features of the independent claims. Embodiments and further aspects of the invention are given by the dependent claims and the subsequent description.

According to an aspect of the invention, a secondary circuit arrangement is provided, which has a secondary coil for transmitting and/or receiving magnetic energy from a magnetic field and for converting the magnetic energy into electrical energy, in particular into current and voltage. The secondary circuit arrangement also has an energy transmission device for transmitting electrical energy, a secondary-side detection device and a terminal switching device or crowbar. The magnetic field is generated by a primary coil of the primary loop arrangement and is coupled into the secondary loop arrangement. For example, the magnetic field is coupled into the secondary coil by a loose coupling with the primary coil of the primary loop arrangement. The energy transmission device has an input for coupling to the secondary winding and furthermore has an output for providing electrical energy as a voltage and/or current. The secondary-side detection device is connected to the input and/or output of the energy transmission device in order to detect an excess pressure at the input and/or output of the energy transmission device. Such an overvoltage, i.e. exceeding a predefinable voltage limit value, can be triggered, for example, by the load at the output of the energy transmission device being relieved. The secondary-side detection device is designed such that it influences the magnetic field in the secondary coil by means of the terminal switching device in such a way that a current and/or voltage jump is caused in the primary coil after the secondary-side detection device has detected an overvoltage at the input and/or output of the energy transmission device.

According to a further aspect of the invention, a primary circuit arrangement is specified, which has an energy generating device for providing electrical energy and a primary coil for converting the electrical energy into magnetic energy. Furthermore, the primary circuit arrangement has a primary-side detection device. The energy generating device is connected to the primary coil, wherein the primary coil is provided for transmitting and/or receiving magnetic energy. Furthermore, a primary-side detection device is connected to the primary coil and is further provided for detecting a current jump in the primary coil and for switching off the energy generating device when a current jump is detected. The current jump may be caused by exceeding a predefinable current limit value.

Also provided according to an aspect of the invention is a system for energy transfer having a vehicle pad module apparatus and a floor pad module apparatus. The vehicle mat module arrangement has a secondary circuit arrangement and the floor mat module arrangement has a primary circuit arrangement, wherein the secondary circuit arrangement and the primary circuit arrangement are coupled, in particular loosely coupled, by means of a magnetic field, i.e. without the use of ferrite cores.

Also described according to an aspect of the invention is a method for testing a secondary circuit arrangement, which first of all has a coupling of the secondary circuit arrangement to a primary circuit arrangement via a magnetic field. The energy to be transmitted is then preset by the secondary circuit arrangement in the form of a preset power, for example via a communication channel. The terminal switching device is triggered or actuated by a drop in a detection threshold value for detecting an excess voltage in the secondary-side detection device, and the current and/or voltage jump resulting from this triggering of the terminal switching device is evaluated in the primary circuit device.

By means of the test method, the functional normality of the secondary detection device can be checked.

According to another aspect of the invention, a method for testing a primary circuit arrangement is described, which has an identification of a coupling to a secondary circuit arrangement. The current jump is then simulated by lowering the detection threshold for detecting a current jump in the primary detection device, and the reaction of the primary detection device triggered by the lowering is evaluated.

By means of this test method, the functional normality of the primary-side detection device can be checked.

It should be noted that without limiting the generality, basically the starting point is that the secondary-side detection device is on the secondary side in the secondary circuit arrangement and the primary-side detection device is on the primary side in the primary circuit arrangement. However, the prefix and/or the terms "primary" and "secondary" should be understood as a name in essence. It is therefore also possible for the secondary-side detection device to be operated on the primary side in the primary loop arrangement and for the primary-side detection device to be operated on the secondary side in the secondary loop arrangement, so that the description also applies to the case of reversal and/or to the reversal propagation direction and/or the triggering sequence for the information flow. The same applies to the test method.

However, this safety function is generally used for secondary side protection, i.e. danger comes from the secondary side, and the primary side must react quickly enough without substantial communication in order to function quickly.

According to a further aspect of the invention, a computer-readable storage medium is provided, on which a program code is stored, which when executed by a processor implements at least one of the methods described. A control device or controller may use such a processor.

A floppy disk, a hard disk, a USB (universal serial bus) memory device, a RAM (random access memory), a ROM (read only memory) or an EPROM (erasable programmable read only memory) may be used as the computer-readable storage medium. As storage medium, ASIC (application specific integrated circuit) or FPGA (field programmable gate array) and SSD (solid state disk) technology or flash memory-based storage media can also be used. A web server or cloud may likewise be used as a storage medium. The communication network may also be considered a computer-readable storage medium, such as the internet, which may allow downloading of the program code. Radio-based network technologies and/or network technologies connected to cables may be used.

According to yet another aspect of the invention, a program element is provided, which, when being executed by a processor, carries out at least one of the methods.

A change in the current and/or voltage relationship and/or power on the secondary side can be brought about by means of the terminal switching device, which change is also evident on the change in the current and/or voltage relationship and/or power on the primary side due to magnetic feedback on the basis of the magnetic coupling between the primary and secondary loop devices. The change in the current and/or voltage relationship and/or the power propagates counter to the propagation direction of the energy and can be detected in the primary circuit arrangement. Changes in current and/or voltage relationships and/or power can be interpreted as information that propagates against the direction of propagation of the energy. For example, the switching and changing of the voltage on the secondary side by means of the terminal switching device is evident as a current jump on the primary side. The current jump contains an information. This information can be evaluated on the primary side of the primary circuit arrangement and used to switch off the energy supply. The information transfer may react higher or faster at the physical level than with a transfer system operating with multiple communication layers, for example with OSI layers (open systems interconnection) or a WLAN (wireless LAN) system. Thus, by evaluating the physical information, the primary loop device can be made to react to interference on the secondary side faster than it can react when using a costly communication system. Thus, the use of physical information can be used to quickly switch off the energy delivery on the primary side.

To distinguish the fast communication channel from the protocol-based communication channel, the term "physical channel" or "physical return channel" should be used herein without limiting the role even when the protocol-based communication channel also uses physical transfer.

The function of the physical return channel can be tested by purposefully manipulating the terminal switching device and by evaluating the state obtained as a result of the manipulation. Thereby, it is also possible to test components included in the physical return channel forming portion, such as a comparator or a control device. Since the correlation of the signal propagation can finally infer the normality of the channel function in both directions.

The physical return channel may be used in parallel with respect to another communication channel, such as in parallel with a protocol-based communication channel. In order that the fast response of the return channel is not slowed down by the software layer, it should be noted in the construction of the physical return channel that essentially only hardware components are used, which have a correspondingly short response time, for example using a comparator. For example, software components operating on the control device or the controller can be used for less time-critical operations, such as for example the adjustment of the switching threshold for the comparator.

According to a further aspect of the invention, the secondary-side detection device for detecting an overpressure has a secondary-side comparator which can be used to build a quick return channel. Likewise, the primary-side detection device for detecting a current jump can have a primary-side comparator.

Alternatively or in addition to the detection of a current jump, it is also possible to detect a voltage jump in the primary resonant circuit by means of a primary-side detection device. The measurement of the voltage jump may be used when the evaluation of the voltage measurement is not made for another purpose.

According to a further aspect of the invention, the secondary circuit arrangement has a secondary-side control device, wherein the secondary-side control device is provided for presetting the limit values of the secondary-side comparator.

In accordance with a further aspect, a terminal switching device of the secondary circuit arrangement is provided, which reacts to at least one protective measure upon detection of an excess voltage at the input and/or output of the energy transmission device, the at least one protective measure being selected from the group of protective measures consisting of: short-circuiting an input of the energy transfer device; short-circuiting the output of the energy transfer device; detuning an energy transfer device; and isolating the tank circuit formed by the secondary coil.

These protective measures result in a load-free resonant circuit, which results in an excessive current on the primary side, which can be detected again.

The secondary-side detection device can in one example be provided for changing the impedance and/or the goodness and/or the resonant frequency of the energy transmission device when an overpressure on the output is detected.

Changing the resonant frequency of the energy transfer device may be performed by switching on and/or off a capacitor in the energy guiding device.

A change in the resonant frequency can cause a detuning of the energy guiding device and thus of the transfer path, so that the output is protected from excessive energy and/or power transfer even if energy is still supplied from the primary circuit arrangement side. Thus, for example, an excess pressure can be reduced or even substantially completely avoided when the load on the output is unloaded by the load.

Furthermore, the energy transmission device may have a rectifying device. The change in the goodness of the energy transfer device may be achieved in this example by shorting the rectifying device.

A short-circuit of the rectifier device can occur at the rectifier device input and result in a transfer oscillation circuit formed by the secondary coil with the capacitor and/or the further coil, so that only a small portion of the energy arriving at the secondary coil is transferred via the energy transfer device. The energy arriving via the secondary coil is reflected by changing the goodness, for example back onto the primary loop arrangement. This reflection can then be detected in the primary circuit arrangement and the primary circuit arrangement can interrupt the energy transfer to the secondary circuit arrangement in order to prevent an overpressure at the output of the secondary circuit arrangement.

In a further example, the secondary-side detection device is provided for providing a command and/or a signal when an excess pressure is detected at the input and/or output of the rectifier device, so that the command and/or the signal can be transmitted via the magnetic field in order to control the energy transmission device to change the magnetic energy of the magnetic field.

Such commands and/or signals can be generated, for example, in the form of reflected energy on a physical level with varying degrees of merit, as a result of which a rapid shutdown of the energy generation can be achieved. Alternatively or additionally, however, such commands and/or signals can also be distributed via further communication channels, for example via a positioning signal channel and/or a protocol-based communication channel, in particular a WLAN communication channel. Since the magnetic field is present substantially only during the energy transfer, the excess pressure can be exchanged via the magnetic field substantially only during the energy transfer to the primary circuit arrangement. By means of a further separate channel, communication can also already be carried out before/after the energy transfer at a point before or after it.

For example, a secondary-side detection device is provided, which, when an excess pressure is detected at the input and/or output of the rectifier, adapts the energy transmission device in such a way that the electrical reactive power is at least partially reflected and transmitted via the magnetic field.

The reflected reactive power can be evaluated by the primary loop device to stop generating energy.

In a further example, a secondary detection device is provided, which interrupts the energy transmission device and/or the secondary coil when an excess voltage is detected at the input and/or output of the rectifier.

In particular, the secondary-side detection device can be provided for actuating a terminal switch, so that the terminal switch interrupts the energy transmission device and/or the secondary coil. Interrupting the secondary coil may also be understood as isolating the tank circuit formed by the primary coil and the capacitor, in addition to opening the physical connection of the secondary coil to the energy guiding device.

Drawings

Further exemplary embodiments of the invention are described below with reference to the drawings.

Fig. 1 shows an inductive charging system according to an exemplary embodiment of the invention.

Fig. 2 shows a block wiring diagram of an inductive charging system according to an exemplary embodiment of the present invention.

Fig. 3 shows a simplified view of the inductive charging system from fig. 2 according to an exemplary embodiment of the present invention.

Fig. 3a shows a simplified block diagram of a secondary loop arrangement according to an exemplary embodiment of the present invention.

Fig. 4 shows a schematic block diagram of an energy transfer system with a fast communication channel according to an exemplary embodiment of the present invention.

Fig. 5 shows a trend of the detection threshold value with respect to the output voltage during a trigger test in a time-voltage diagram according to an exemplary embodiment of the present invention.

Fig. 6 shows a block wiring diagram of a primary side comparator according to an exemplary embodiment of the present invention.

Fig. 7 shows a time-voltage diagram of detection thresholds that can be preset by means of a primary-side comparator for a functional test of the primary-side comparator, according to an exemplary embodiment of the present invention.

Fig. 8 shows a flow chart for a method for testing a primary loop arrangement according to an exemplary embodiment of the invention.

Fig. 9 shows a flowchart for a method for testing a secondary loop arrangement according to an exemplary embodiment of the invention.

Detailed Description

The illustrations in the drawings are schematic and not to scale. In the following description of fig. 1 to 9, the same reference numerals are used for the same or corresponding elements.

In this context, the terms "capacitor" and "capacitance" and "coil" or "choke" and "inductance" can be used in the same sense and should not be interpreted restrictively unless otherwise stated. Furthermore, the terms "energy" and "power" may be used equivalently and should not be construed restrictively unless otherwise stated.

Fig. 1 shows an inductive charging system 100 or a system 100 for energy transfer according to an exemplary embodiment of the invention. In this case, a side view is shown, which is directed to a system for contactless charging of an electric vehicle. Beneath the vehicle chassis 102 is a vehicle mat module (CPM)104, which is used to supply the vehicle 102 with electrical current. For energy transfer, a magnetic field 106 is used, which inductively supplies energy to a floor mat module (GPM)105, which is mounted on the floor 103. The energy required for charging is taken from the main connection 107, which may be not only an Alternating Current (AC) but also a Direct Current (DC). For the communication between CPM104 and GPM105 a separate connection 101 is used, which may for example use a wireless protocol like WLAN (wireless LAN) or NFC. This connection can be used as a feedback channel 101 or as a communication channel 101 through which CPMs 104 and GPMs 105 can exchange information. Not only the magnetic field 106 for energy transfer, but also the wireless signal 101 are electromagnetic waves, but they have different frequencies.

A block wiring diagram of an inductive charging system 100 according to an exemplary embodiment of the present invention is shown in fig. 2. A system for inductive energy transfer is considered, which can be used for contactless charging of an electric vehicle. In such a system, the magnetic alternating field 106 is generated in a frequency range of, for example, 25.. 150 kHz. It must be taken into account here that the limit values for the electromagnetic emission can be established outside this frequency band by international valid standards. In order to comply with these limit values, it is decisive that the alternating magnetic field 106 operates with fundamental oscillations in the range of 25.. 150kHz and contains only very small higher harmonics.

On the other hand, however, the efficiency of the power transfer should be as high as possible and therefore a square-wave signal with the fundamental frequency of the magnetic alternating field is generated with electronic switches inside the inverter 201, for example by means of MOSFETs, IGBTs, since very little losses are thus obtained. However, square wave signals contain considerable higher harmonics. These higher harmonics can be very well filtered out with a filter 200, for example an LC filter 200. The filter 200 may be implemented differently here. For example, a 4 th order filter 200 is shown in fig. 2, but other arrangements of capacitors and coils are possible. An input current l is applied to the input 206 of the filter 200_inAnd an input voltage U_in. The filter 200 has two parallel input coils La₁And La₂And a filter input capacitor Ca and an output coil Lb connected in parallel₁And Lb₂And a filter output capacitor Cb. Instead of two input coils La connected in series₁And La₂A single input coil La may also be used. Instead of two input coils Lb connected in series₁And Lb₂A single input coil Lb may also be used.

The filter in the primary circuit is constructed in such a way that it has substantially no influence on the implementation of the secondary circuit arrangement. As shown in fig. 3, energy transfer system 100 may also operate with a variable input impedance without a filter. The input impedance may also be zero Z1-0.

Input coil La₁And La₂Directly connected to the output of the inverter 201. In this case, it can directly mean that no further structural elements are coupled in between. In this case, the capacitors connected in series should not change a direct connection into an indirect connection.The term "directly" may in particular be used to indicate that the joint points of the respective components are uniform and/or have the same electrical potential. An output coil Lb at the output 207 of the filter 200₁And Lb₂Directly connected with the coil La₁And La₂And to the primary resonant tank 202. The primary resonant tank 202 is supplied with a voltage U1 and a current l1 or lL, which is derived from the alternating current generated by the inverter 201. Based on the filtering action of the filter 200, the primary current l1 and the primary voltage U1 have a sinusoidal course.

The primary resonant tank 202 has a primary resonant coil L1 or a primary coil L1 and a primary resonant capacitor C1221. The primary resonant tank 202 converts the current l1 and the voltage U1 into the magnetic alternating field 106. The magnetic alternating field 106 couples into the secondary resonant circuit 203 with a coupling factor k and transfers the energy from the primary coil to the secondary resonant circuit 203 by means of resonant and inductive energy transfer.

The secondary resonant tank 203 has a secondary resonant coil L2 or a secondary coil L2 and a secondary resonant capacitor C2222. Since the secondary resonant tank 203 is set to the resonant frequency of the primary resonant tank 202, the secondary resonant tank 203 is excited into oscillation by the magnetic field 106 to such an extent that a secondary current l2 and a secondary voltage U2 are obtained. They are fed to a rectifier 204 or rectifier 204, which can provide the direct voltage of a load 205, for example a battery 205, an intermediate circuit 205, a traction circuit 205 or an output HV-DC205 on the CPM104 side, at its output 220.

The inductive charging system 100 is supplied via a DC Voltage source 107 or an input HV-DC (High Voltage Direct Current) or via an ac Voltage 107.

The energy transfer system 100, for example the ICS system 100, has a base station 105 or GPM105, a remote device 104 or CPM104, wherein the base station 105 and the remote device 104 may be loosely coupled to each other through an inductive coupling and a feedback channel 101. The CPM104 can be positioned relative to the GPM105, starting from a loose coupling.

The base station 105 or GPM105 has a primary loop 202 and the remote device 104 or GPM104 has a secondary loop 203. The primary loop 202 has coil L1 and the secondary loop has coil L2. If coils L1 and L2 are close to each other, the magnetic field 106 generated by the coils may pass through the respective other coils L1, L2. The magnetic field forms an inductive coupling with a coupling coefficient k or a coupling coefficient k through the parts of the respective further coils L1, L2. This coupling forms a loosely coupled transducer 211. The portion of the magnetic field 106 outside the respective further coil L1, L2 forms a stray capacitance. The smaller this part of the stray capacitance formed, the larger the coupling coefficient k. However, since the movability of the GPM105 and the CPM104 relative to each other cannot form a transformer with a core in which the coupling coefficient k is substantially constant, the coupling coefficient is variable in the case of a loosely coupled transformer and is, for example, related to the relative pose of the GPM105 and the CPM104 relative to each other.

Fig. 3 shows a simplified view of an inductive charging system 100 or a system 100 for energy transfer according to an exemplary embodiment of the present invention. The regulation of the ICS system 100 can help ensure functional security in the ICS system. Provisions may be made to protect the environment from too strong magnetic radiation based on the strong magnetic field 106 being used for power transfer. The specification may set, for example: the field 106 generated by the GPM105 is cut off in the absence of the CPM104, or after 2 seconds (2s) at latest when the CPM104 is disadvantageously coupled with the GPM and the field 106 is cut off. Thus ensuring that: it can be confirmed within the 2 second time window that the GPM105 and CPM104 are coupled as specified by the field 106. Otherwise the field 106 may be switched off.

The WLAN 101 used for communication between the GPM105 and the CPM104 may have a cycle time of up to 300 milliseconds (ms). It can be ensured by feedback via channel 101 that CPM and GPM are also coupled. If the vehicle should be driven away and the CPM should not receive power from the GPM, then this is recognized and power delivery to the GPM is disabled. Even if the signal via the return channel 101 disappears for 2 seconds, the energy transfer can be suspended in view of safety, since it cannot be ruled out that the signal disappears due to a loss of coupling or a damage to a component of the return channel 101.

The start of the inductive charging is performed by the inverter 201 or PWM (pulse width modulation) generator 201 with a constant Duty cycle (Duty-Zyklus) and a variable frequency, wherein the variable frequency relates to a frequency shift. The starting frequency of the PWM generator 201 is set at the maximum possible frequency in order to set the maximum possible reduction between the input variable, i.e. the duty cycle (Dutycycle) and the output variable, of the primary part 202 of the GPM 105.

If a suitable operating point is found, resonance is formed between the primary part 202 and the secondary part 203 and energy can be transferred between the primary part 202 and the secondary part 203 via the field 106. Depending on the operating point, this operating or resonant frequency occurs between 81.35kHz and 89.5 kHz.

Charging is not possible if, after passing through one of these frequency bands, a predefinable minimum power is not detected with a constant duty cycle or duty cycle. Thus, if the GPM105 is not above the minimum threshold while delivering power, the power received by the CPM104 is still suspended from this startup process of inductive charging. Thus, charging is turned off or blocked with little coupling between the GPM105 and CPM 104. Such a small coupling may be obtained with large shifts between the GPM105 and CPM 104. As a result of a preset characteristic, the time interval for the start-up process does not exceed a predefinable value of, for example, 2.0 seconds. This immediate suspension of the charging process during the startup phase without reaching a pre-settable minimum power can result in security at startup of the ICS 100 without requiring communication between the GPM105 and the CPM 104.

The greater the spacing between the GPM105 and CPM104, the less power or energy may be delivered at a lower frequency. That is, the greater the spacing between the GPM105 and the CPM104, the smaller the resonant frequency, or stated differently, the resonant frequency is related to the spacing between the GPM105 and the CPM 104.

However, if a charging process is performed and the coupling between the GPM105 and the CPM104 is continuously confirmed by the regulation loop 210 using the feedback channel 101, an over-voltage condition may occur at the output 220. This is because magnetically coupled systems, particularly magnetically loosely coupled system 100, have similar system behavior as current sources. The inductive charging system 100 involves a loosely coupled system because of the mobility of the GPM relative to the CPM. This means that the system 100 for energy transfer or the system 100 for inductive charging likewise has a high internal impedance at the output 220, like a current source. With the load 205 unloaded, the system 100 therefore further attempts to drive current into the output 220. In the event of a Load Dump (Load Dump) or Load unloading, for example when a fuse in the vehicle is triggered, the plug is released, the line is broken or the battery protection relay is opened, the excited resonant circuit on the ground mat module 104 side and its direct further excitation cause the system to act on the output 220 as a current source with a high internal resistance on the DC intermediate circuit of the vehicle, which is connected to the output 220 and is illustrated in fig. 3 by the Load 205. The part of the energy stored in the tank circuit is thus discharged into the high impedance output 220, which can generate a very high voltage on the output 220 by means of a small capacitance of the output 220. This voltage may be much higher than the operating voltage and the design voltage of the respective switching circuits in the vehicle, which are coupled to the output 220, for example devices such as DC/DC converters or motor converters, which are coupled to the DC circuit at the output 220 and are illustrated by the resistor 205. This further driving causes the voltage on the output 220 of the delivery system 100 to be very high. Due to this voltage excess based on load shedding, components, such as rectifiers or filters, on the output of the transmission system 100 are destroyed as a result of the excess voltage.

In order to prevent damage occurring during the intended operation as a result of the output voltage at the output 220 exceeding a predefinable limit value, the secondary circuit arrangement according to the invention provides a crowbar 301, a terminal switching device 301 or a protective device 301 at any point on the secondary circuit arrangement 104'. The protection device 301 detects a load drop at the output 220 of the energy transmission system 100 and very quickly reduces the active power transmitted to the output 220 and/or stops the energy transmission. The protection device 301 can use not only hardware components but also software components for fast reaction. However, in order to bring about a rapid response, the use of software components is to the greatest possible extent dispensed with.

Fig. 3a shows a simplified block diagram of a secondary loop arrangement according to an exemplary embodiment of the present invention. The terminal switching device 301 or crowbar 301 may be used at any location on the secondary loop device 104'. As shown in fig. 3a, it is feasible that when S1 is opened, the crowbar 301 can also be switched between different capacitive configurations, e.g. 222a, 222b, which substantially correspond to the capacitor 222. By this form of switching, a detuning occurs when the crowbar 301 is triggered, as a result of which the resonant frequency of the secondary resonant circuit 203 can be shifted strongly relative to the resonant frequency of the primary resonant circuit 202 and thus the current on the secondary resonant circuit is reduced in the case of an active source on the primary side. The resonant frequency of the secondary resonant tank 203 and the primary resonant tank 202 is approximately 85kHz when they are used for energy transfer. If S1 is closed and the total capacitance of the secondary resonant capacitors C2, 222a, 222b is reduced, for example due to the switching-on of the series capacitance 310 in series with S1, the resonance frequency of the CPM, in particular the resonance frequency of the secondary resonant tank 203, rises and is further away from the primary resonance than would occur without the series capacitance 310, whereby very good protection characteristics for the system 100 can be achieved. In another example, capacitor 222b, which is a sub-capacitor of secondary resonant capacitor 222, may also be turned off when terminal switching device 301a is short-circuited by means of switch S1.

To reduce the applied power delivered to the output 220 and/or to stop energy delivery, different application mechanisms may be used, alone or in combination.

One possibility to stop the energy transfer is to use the feedback channel 101 after detecting the load unloading on the output 220 of the energy transfer system 100 in order to command the energy transfer on the primary side to be switched off by means of a command or instruction via the channel 101, for example the WLAN channel 101, onto the energy transfer system input. However, because the channel 101 may use a communication protocol at a higher level of the OSI protocol, the indication may slowly flow onto the primary loop device 105'.

Fig. 4 shows a schematic block diagram of a system 100 for energy transfer with a fast communication channel according to an exemplary embodiment of the present invention. In particular, three paths with associated components are shown in the block diagram.

The

energy transfer paths

106, 106a, 106b, 106c, 106d, 106e, 106f, 106g extend from the energy source 107 via the energy input 106a, via the power electronics 401 and via the section 106b to the primary-side current and/or voltage measuring device 402 and via the section 106c to the primary coil L1. The primary side current and/or voltage measurement device 402 may be part of the primary side detection device. The primary-side current and/or voltage measuring device 402 is provided in particular for measuring the current L1 in the coil L1. Electrical energy is converted to magnetic energy in coil L1 and transferred to secondary coil L2 by magnetic field 106. Via the energy transfer section 106d, the energy, which is in turn converted into electrical energy in the form of current and voltage, is passed at the terminal switching device 301 and is supplied to the secondary-side power electronics 403 via the energy path section 106 d. The power electronics 403 have components for forming the output voltage and the output current, such as the rectifier 204 and filter components. The terminal switching section 301 and the power electronics 403 basically form an energy transfer device 405. Energy is provided at the output 220 of the system 100 for energy transfer via the

energy path sections

106f and 106g and the secondary-side current and/or voltage measuring device 404. The secondary side current and/or voltage measurement device 404 may be part of a secondary side detection device.

Extending in the opposite direction with respect to the

energy paths

106, 106a, 106b, 106c, 106d, 106e, 106f, 106g is a communication channel 101, which may use, for example, a wireless protocol such as WLAN. However, by using a protocol, the communication channel 101 or the feedback channel 101 is slow. The feedback channel 101 is formed between the primary-side control device 406 and the secondary-side control device 407, in particular by the primary-side and secondary-side communication devices contained therein.

For fast feedback, the secondary side comparator 409 and the primary side comparator 408 may communicate through a physical return channel 101'. The physical return channels are arranged in opposite directions relative to the

energy pathways

106, 106a, 106b, 106c, 106d, 106e, 106f, 106g via the magnetic field 106 during energy transfer.

This physical return channel 101' can be used to recognize load shedding on the output 220 of the energy transmission system 100 and to drastically reduce or even completely stop the transmitted operating power 106g very quickly, substantially using hardware instead of software, in order to react, for example, to load shedding on the output 220.

The secondary-side comparator 409 can directly control the terminal switch 301 via the control line 101 ″ in order to prevent damage on the secondary side or the CPM104 by triggering the secondary-side terminal switch 301 or the CPM-side terminal switch arranged, if it detects a load drop on the output 220 via the secondary-side voltage and/or current sensor 404 or the secondary-side current and/or voltage measuring device 404 and the measuring link 101 ″.

The triggering of the crowbar is not provided for protecting the primary side, but for the output of the secondary side. The primary side represents an energy source and then prevents the system reaction effects of a short circuit by turning off itself via detection of crowbar triggering.

Due to the magnetic coupling between the primary circuit arrangement 105 ' and the secondary circuit arrangement 104 ' by the magnetic field 106, an event of actuating the terminal switching device 301 or the crowbar 301 is effected directly on the primary side via the physical return channel 101 ' and in particular via the influence of the magnetic field 106, that is to say the reaction speed corresponds substantially to the propagation speed of the magnetic field. In particular, the influence of the magnetic field 106 becomes apparent via the primary-side current and/or voltage sensor 402 in the primary-side comparator 408 as a current change or current jump, which can be further output via the primary-side measuring link 101 "" from the primary-side current and/or voltage sensor 402 or from the primary-side current and/or voltage measuring device 402 onto the primary-side comparator 408. If a predefinable threshold value or a predefinable limit value in the primary-side comparator 408 is exceeded, the primary-side comparator 408, via the control line 101 "" 'and the actuation of the shut-off device 410, causes the primary-side power electronics to be shut down and thus the energy supply to the secondary circuit arrangement 104' to be stopped.

The feedback channel 101 provided for communication between the CPM104 and the GPM105, which uses a communication protocol such as WLAN and is therefore slow, can be bypassed by using a physical return channel 101'. Bypassing the slow connection can be used for fast triggering of modes of operation that require fast reaction times. Because the feedback channel 101 may be too slow for this mode of operation because the protocol-based return channel only allows communication with high latency and cycle time compared to the required emergency stop time, which should be below 2 milliseconds (< 2 ms). Furthermore, in the case of the protocol-based communication channel 101, it must therefore be estimated that some message packets used to satisfy the protocol presets fail or are disturbed and are thus prevented, i.e., that a shutdown message occurs on the primary side, which indicates a source of danger by supplying energy when the load is unloaded or suddenly dropped.

The physical channel 101' thus represents a quick variant for the communication of time-critical events, which can be used in parallel to the feedback channel 101 in order to ensure an immediate shut-down, for example in the case of load shedding or when an emergency shut-down is required.

Thus, for example, two redundant shutdown systems within the system 100 for energy transfer can also be implemented. The first shutdown system may have a primary-side control device 406, a secondary-side control device 407 and a second primary-side measuring link 101a and a second secondary-side measuring link 101b, which are connected to the primary-side current and/or voltage measuring device 402 or the secondary-side current and/or voltage measuring device 404. The control means 407, 406 may have a processor, microprocessor or controller. The second shutdown system may have a primary-side comparator 408, a secondary-side comparator 409 and a first primary-side measuring link 101 "", as well as a first secondary-side measuring link 101' ", which are likewise connected to the primary-side current and/or voltage measuring device 402 or the secondary-side current and/or voltage measuring device 404.

By using the direct shutdown pathways 101 ', 101 "', 101" "', the second shutdown system has a smaller latency and greater reliability than the first shutdown system, which uses the shutdown pathway 101 via the WLAN.

When an emergency scenario and/or real-time behavior is planned, it should be taken into account that, when the load on the output 220 is switched off in the event of a load unloading situation, the output voltage at the output 220 rises very strongly within 2 milliseconds and the primary side should switch off the energy delivery within a period of 2 milliseconds in order to prevent exceeding the maximum output voltage at the output 202. It should furthermore be taken into account that the WLAN connection 101 may be completely disturbed and switched off after a connection timeout, for example after 2 seconds, since the fault protocol may provide that the entire system 100 for energy transfer is switched off and started by a defect in the transfer path 101 only if no message has occurred after a period of 2 seconds. However, within 2 seconds, the output voltage at output 220 may reach a limit value that may cause damage to components of system 100 used for energy transfer. The suspension of the WLAN module also occurs because the WLAN module is not authenticated as ASIL (car safety integrity level).

In order to ensure a fast response time, the rise in the output voltage is therefore compared by the secondary-side comparator 409 with respect to a limit value or threshold value that can be set by the secondary-side control device 407 when the secondary-side detection device 409 detects a load unloading at the output 220 by means of the voltage sensor 404. As soon as the voltage at the output 220 exceeds a predefinable limit value or a predefinable detection threshold, the terminal switching device 301 is triggered. Triggering the terminal switching device 301 generates a current jump on the primary side 105', in particular in the primary coil L1. The current 11 of the main magnetic field 106 is again compared on the primary side 105' with a primary-side comparator with respect to a limit value that can be set by the primary-side control device 406. The primary-side current and/or voltage measuring device 402 can be designed as a current sensor 402 for detecting the current. If the measured current value caused by the secondary-side triggering of the terminal switching device 301 exceeds a predefinable limit value, the drive of the power electronics 402 is automatically deactivated by the shut-off device 410.

The "short-circuit effect" of the terminal switching device is noticeable as a current and/or voltage jump, in particular due to a current and/or voltage increase on the primary side. If the load 205 is switched off, the input voltage Uin becomes larger with respect to the resonant current l1 via the strengthening (gain) of the filter 200 and causes the current in the primary resonant tank 202 to rise. This current increase takes place with the same control voltage Uin over the reaction time and results in a higher current l 1.

In one example, the physical return channels 101 ', 101 "', 101" "', 404, 409, 301, 402, 408, 410 may have substantially only logic circuit modules. The entire logic circuit of the return channels 101 ', 101 "', 101" "', 404, 409, 301, 402, 408, 410 is subjected to self-testing and/or functional testing before each start of a charging process.

Fig. 8 shows a flow chart for a method for testing a primary loop arrangement according to an exemplary embodiment of the invention. The method starts in an idle state S801. In state S802, an identification of the coupling of the primary circuit arrangement to the secondary circuit arrangement is made. Before the energy transfer is started, in state S803 the detection threshold or a limit value for detecting a current jump is reduced in the primary detection device 408 in order to thereby simulate a current jump. In a further state S804 of the method, the response of the primary detection device 408 is evaluated, for example, by means of a primary-side control device, and it is determined whether the primary-side detection device 408 is functioning properly. Thereafter, the method returns to the idle state S805.

In other words, the limit value of the primary-side comparator 408 is preset by the primary-side control device 406 using a PWM signal (pulse width modulation) via the primary-side control link 411 in such a way that the limit value of the current is exceeded, as a result of which a current jump, i.e. a change in the current value, can be simulated.

The difference in amplitude between the limit value and the present current value is used to trigger the comparator. The pulse duration or any further time constant of the current jump is not substantially evaluated. The limit values generated by the primary control device 406 are far apart from one another with reference to a predetermined time and a time of the reaction to the crowbar trigger. The reference threshold value or limit value for the detection is preset by the control device 407 on the order of milliseconds on the primary-side comparator 408, and the response of the comparator 408 to exceeding the limit value is carried out in the microsecond range for approximately 10 us.

The PWM signal has a duty cycle, wherein a duty cycle of 50% corresponds to a predefinable current limit value of 0A. In another example, from ] 0%; a duty cycle selected in the range of 100% ] or a duty cycle greater than 0% may be interpreted as a predefinable current boundary value of 0A. Before each start of a charging process, as long as the coil current L1 in the primary coil L1 is 0A, i.e. as long as no current flows and no energy is transferred, but a magnetic field is already built up, a current limit value of less than 0A is set at the input of the primary-side comparator 408, wherein the standard-compliant duty cycle is set from a value regulated in a standard-compliant manner of more than 50% (> 50%) to a value of less than 50% (< 50%), so that the current of 0A exceeds the predefinable current limit value of less than 0A. The adjustment of the different duty cycles is also shown in fig. 7.

The limit value is set by the microcontroller or control unit 406 as a function of the current effective value of l 1. This limit value is updated with a very slow time constant and the current filtered measured value l1 is adjusted with an offset as the limit value for the primary comparator 408. After triggering the comparator 408, this triggering is performed by means of the control device 406. For example, after triggering the comparator, the storage state of the latch or the sample-and-hold mechanism used in the comparator is changed from logic state 0 to 1. This state can then be set to 0 again by the control unit 406 after the analysis via the control line 411 or the reset line 411. As soon as the state of logic 1 is applied, the source 107 is blocked by hardware by means of the shut-off device 410 and thus deactivates the drive 401. By means of the primary control device 406, it can be checked whether the shut-off device 410 is actuated and thus can be evaluated whether the primary comparator 408 is triggered. The functional normality of the primary side comparator 408 can be checked by this test method.

Fig. 9 shows a flowchart for a method for testing a secondary loop arrangement according to an exemplary embodiment of the invention. The method starts in the idle state S901. In state S902, the secondary loop arrangement 104 'is coupled with the primary loop arrangement 105' via the magnetic field 106. In state S903, energy to be transferred in the form of a predetermined power is set on the primary circuit device 105' by the secondary circuit device. The presets may be sent, for example, via the feedback channel 101. By this presetting, the secondary circuit arrangement requires a presettable power in the case of the primary circuit arrangement 105'. In state S904, the terminal switching device 301 is triggered in that the detection threshold or limit value for detecting an excess pressure in the secondary detection device 409 is lowered. The detection threshold value can be transmitted from the secondary-side control device 407 via the secondary-side adjustment and/or interrogation link 412 to the secondary-side detection device 409. Furthermore, the current jump in the primary circuit arrangement 105', in particular in the primary-side detection arrangement 408 and/or in the primary-side control arrangement 406, is evaluated. Thereafter, the test method terminates in the idle state S905. The test method for the secondary circuit arrangement 104' requires that a magnetic field 106 is built up and that a non-hazardous energy or power transfer of, for example, 500W takes place. A physical return channel 101' may be established by the magnetic field 106.

In other words, in order to test the secondary circuit device 104 'to send a command for the secondary circuit device 104' and the primary circuit device 105 'via the feedback channel 101 or the WLAN channel 101, the command causes the primary circuit device 105' to set up a charging power of, for example, 500W on the secondary side within 2 seconds.

A constant power of 500W was adjusted before the test method was performed. The adjustment of the constant power results in: the protection means, in particular the

comparators

408, 409, are only tested when active power is being transmitted, i.e. the test is premised on the fact that the

resonant circuits

202, 203 are coupled and a load is present. If the coupling is too deep, i.e. if a small coupling factor is determined, which runs to zero (k → 0) or if no load is coupled, for example if only a capacitance is present at the output 220 but no battery 205 is present, then an excess current l1 is obtained without actuation of the terminal switching device S1302 or exceeds the limit value set in the comparator 408 in the primary device 105', i.e. the comparator is triggered as a result of the excess current. The detection device 409 or the primary-side control device 409 is only concerned with an indication about the exact functionality of the mechanism when the operating power can be successfully set before.

The secondary side control means 407 measures the voltage value at the output 220, which is obtained at a regulated power of, for example, 500W. The voltage measurement on the output 220, on which the HVDC switching circuit and/or the battery can be coupled, is carried out by means of a current and/or voltage measuring device 404, which in this case is implemented as a voltage measuring device 404. After the current value of the output voltage is known by the secondary control device 407, the secondary control device 407 reduces the detection threshold for the secondary comparator 409 of the terminal device 301 via the secondary adjustment and/or interrogation link 412. The voltage value is reduced to a voltage value lower than the voltage value previously measured as the output voltage value on the output 220, as the battery voltage or as the HVDC voltage value. By reducing the detection threshold below the currently applied output voltage value, the voltage at the analog output 220 rises after load shedding and switches the secondary-side comparator 409, as a result of which the terminal switching device 301 is triggered, in particular switched.

FIG. 5 illustrates a trend of trigger or probe thresholds relative to output voltage during a trigger test in a time-voltage graph according to an exemplary embodiment of the present invention. In the diagram, time in ms is plotted on the abscissa and voltage in V is plotted on the ordinate. Furthermore, the voltage profile of the output voltage, the battery voltage or the HVDC voltage is shown as curve 501, which has a substantially constant profile over time. The voltage profile of the predefinable secondary-side detection threshold, the predefinable secondary-side limit value or the predefinable secondary-side trigger threshold is illustrated as curve 502. In order to be able to perform a functional test of the terminal switching device 301 despite the constant voltage profile 501 of the output voltage at 400V, the detection threshold for the value of 430V is reduced to below 400V.

A functional test is started at time point 503 and the current value of the output voltage 501 is measured. In this case, for example, a voltage value of 400V is determined. Starting with the reduction of the predefinable detection threshold, a waiting time of approximately 400ms, for example, up to time 504 is carried out. Starting from time 504, the predefinable detection threshold is linearly reduced until it reaches the output voltage value, for example after a maximum of 500ms, and after this value it causes the triggering of the terminal switching device 301.

The trigger terminal switching means 301 or the switching terminal switching means 301 can be detected by the secondary-side control means 407 via the adjustment and/or interrogation link 412 and via the secondary-side comparator 409 and indirectly via the terminal switching means 301. The control device 407 is connected to the latch or memory module of the comparator 409 via an adjustment and/or interrogation link 412. The memory module acquires the state of the terminal switching device 301 after the comparator is triggered and remains in this state until the secondary-side control device 407 has erased the memory module again, for example by resetting. The adjustment and/or interrogation link 412 may be used to erase a memory module in the comparator 409.

Since the detection threshold of the secondary side control device 407 has been reduced, the secondary side control device 407 knows which voltage value 502 triggered the terminal switching device 301 at time 505. This voltage value corresponds to the voltage measurement with the secondary side comparator 409. This voltage measurement is present in the secondary-side control device 407, as is the output voltage 501 obtained at the start of the method. Both voltage measurements are carried out by means of the secondary-side voltage measuring device 404, but at different points in time and/or in the case of different measuring methods, for example a first measuring method, implemented and set in analog form, by the secondary-side comparator 409, and a second measuring method, implemented and carried out in digital form, by the secondary-side control device 407.

The initial voltage measurement is known by the secondary-side control device 407 via the secondary-side measurement link 101b and the voltage measurement performed by the secondary-side comparator 409 is known via the measurement link 101' ″. The voltage measurement of the secondary-side control device 407 can now be compared with respect to the voltage measurement of the secondary-side comparator 409 after the comparator in the secondary-side control device 407 has been triggered.

The output current at the output 220 can be known by means of the secondary-side current and/or voltage measuring device 404 via the secondary-side measuring link 101b by means of the secondary-side control device 407. In order to authenticate the exact functional manner of the secondary circuit arrangement 104', the secondary-side control device 407 has to ascertain that the output current at the output 220 is switched off, i.e. falls substantially to 0A with a tolerance of + -0.3A, in the same or the next measuring cycle as the secondary-side control device 407 recognizes the triggering of the terminal switching device 301. The disconnection of the output current certifies the exact functioning of the protection mechanism. When the output current is 0A, the output is then clearly separated with a very high probability, i.e. the protection means has exactly performed the function and can validate this effect. If the disconnection of the output current is confirmed, the secondary side control device 407 may issue from the function normality of the terminal switching device 301. If the disconnection of the output current is not detected, the secondary control device can conclude a fault in the terminal switching device and indicate a defect and/or stop the charging process.

The current l1 in the primary resonant tank 202 is also raised by triggering the terminal switching device, which generates the primary magnetic field 106. The current increase or current jump and optionally also a voltage jump are further output by the primary-side current and/or voltage measuring device 402 to a primary-side comparator 408, which actuates a shut-off device 410. The secondary-side control means 407 can thus wait, within a defined time, after its triggering of the terminal switching means 301, for example via the communication channel 101 to be informed of an emergency shutdown of the shutdown means 410 via the primary-side comparator 408.

If the current i 1 in the coil L1 does not rise in a jump-like manner, i.e. the current does not exceed a predetermined limit value, the primary-side control device 406 does not permit a longer charging within the existing WLAN connection. As long as the components 105 ', 104 ' are connected via the communication channel 101, in particular via the WLAN, the primary component 105 ' follows the direction of the secondary component after a certain time. If, on the other hand, no established communication channel 101, for example an established WLAN connection, is present, a transition to a safe failback safe state, a fault and/or a standby state takes place after 2 seconds. That is, when the primary component 105 'does not acknowledge the current rise, the secondary component continues to operate the crowbar 301 and waits until the primary component 105' reaches a time-out. If the fault condition is reached, the crowbar triggered diagnostics pass the comparator 409 information to the control device 407 that it is failed, or that no confirmation of the primary part or a confirmation signal, e.g. that an excess current l1 has been identified, is obtained. When the communication channel 101, for example a WLAN connection, fails in the meantime, the primary part 105' enters a secure state anyway after 2 seconds.

The corresponding situation may apply to voltage jumps.

If the primary-side comparator 408 does not cause a switch-off of the drive 401, although the terminal switching device 301 has been triggered, the generation of the magnetic field 106 is terminated via the actuation of the switch-off device 410 by means of the primary-side control device 406 and no further charging is permitted anymore, since the physical return channels 101 ', 101 "', 101" "', 404, 409, 301, 402, 408, 410 and/or parts thereof appear to be defective.

Fig. 6 shows a block diagram of a primary-side detection device, in particular a primary-side comparator 408, according to an exemplary embodiment of the invention. The primary side comparator 408 obtains a measured value of the current l1 via a current measuring coil 601 of the primary side current and/or voltage measuring device 402. The current is measured indirectly by the voltage on the current measuring coil 601. The current measuring coil 601 is magnetically coupled to the primary coil L1 and forms a transducer with the primary coil L1. A shunt 602, which is arranged parallel to the current measuring coil 601 and is connected to the potential UZM, protects the primary comparator 408 from an overpressure. Via the measuring link 101 ″, the measuring voltage corresponding to the current l1 is supplied to the primary-side comparator 408, which is implemented as a dual comparator or as a symmetrical comparator with two

operational amplifiers

408a, 408 b. The measurement voltage is supplied to the positive input of the first operational amplifier 408a and the negative input of the second operational amplifier 408 b.

By adjusting the link 411, each of the

operational amplifiers

408a, 408b obtains a predefinable primary-side detection threshold via the PWM signal. The PWM signal is supplied to the negative input of the first operational amplifier 408a and the positive input of the second operational amplifier 408 b. The

outputs

603a, 603b of the two

operational amplifiers

408a, 408b are combined and fed to a latch 604. The latch 604 may be reset via a reset line 605 and implemented as a sample-and-hold mechanism to provide a stable value on the control line 101 ""' for comparing the current value 11 with the primary side detection threshold. The control line 101 ""' is active if a current jump is identified on the primary side, that is to say the voltage value on the first primary side measurement line 101 "", exceeds the voltage value or positive boundary value of the positive peak detection threshold provided by the adjustment link 411. The comparison is performed using positive and negative analog peak measurements of the current. The control line 101 ""' is connected to the shut-off device 410 (the shut-off device 410 is not shown in fig. 6). Since all the components of the comparator 408 shown in fig. 6 are constructed with discrete structural elements, a rapid detection of the voltage jump of l1 can be carried out.

The PWM signal is analog converted by an analog component (not shown in fig. 6) into an analog dc voltage, which is used as a detection threshold and is provided via an adjustment link 111. The detection threshold is positively compared with a positive peak of the current, in particular the voltage at 101 ″, which corresponds to the current, and as a negative threshold with a negative peak of the current, in particular the voltage at the measurement link 101 ″, which corresponds to the current. In this case, the entire voltage is defined with respect to a relational or reference potential UZM, for example GND or 0V of the circuit. The shunt 602 is connected to the UZM. The current measuring coil is used for current measurement in the primary circuit. The design of the primary-side converter 408 also corresponds to the design of a secondary-side converter, which measures the current at the output 220 via a current measuring coil. The current measuring coil 601 of the secondary comparator 409 can be assigned to the current and/or voltage measuring device 404.

The output of the memory block 604 or latch 604 has the function of reporting the memory state and at the same time turning off the driver according to this state. The latch 604 can be implemented as a Flip-Flop (Flip Flop) having a positive output Q101 ""' and a negative output Qneg having the negative value of the positive output 101 "".

Fig. 7 shows a time-voltage diagram 700 of detection thresholds that can be preset by means of the primary-side comparator 408 for a functional test of the primary-side comparator according to an exemplary embodiment of the invention. The time is shown on the abscissa of the diagram and the voltage value is shown on the ordinate with respect to the relationship potential UZM. The time axis is allocated to 5 time ranges I, II, III, IV, V. Curve 408a 'describes the course of the detection threshold value on the primary side, which can be set by means of first operational amplifier 408a via adjustment link 411, for current l1 as voltage course 408 a'. Curve 408b 'describes the course of the detection threshold value on the primary side, which can be set by means of first operational amplifier 408a via adjustment link 411, for current l1 as voltage course 408 b'. The curve 601 'describes the voltage profile of the signal received in the first primary-side measuring line 101 ″, via the measuring coil 601 or the current sensor 601, whether the voltage profile 601' is proportional to the primary current l 1. The measurement signal 601' is sinusoidal and has a primary coil frequency of 85 kHz.

The predefinable primary-side lower detection threshold 408a 'and the predefinable primary-side upper detection threshold 408 b' can be adjusted essentially between the voltage values UZM, xUZM and yUZM, which each relate to the potential UZM.

Range I corresponds to 0% of the duty cycle of the PWM signal provided by the adjustment link 411 and gives an inactive state. Range II corresponds to the duty cycle of the PWM signal provided by the adjustment link 411 which can vary between 0% and below 50% and also gives an inactive state.

In range III, the duty cycle is adjusted by 50% for the PWM signal supplied via the adjustment link 411 and an active state is assumed, in which the predefinable primary detection threshold corresponds to a primary current l1 of 0A. The primary comparator 408 may operate in range III to perform a test method for the functional normality of the primary comparator 408.

In the range IV, a duty cycle of between 50% and 100% is set for the PWM signal supplied via the setting link 411 and an active state is provided, in which the predefinable primary detection threshold corresponds to a primary current l1 of 0A to 100A.

In the range V, a duty cycle of 100% is set for the PWM signal supplied via the setting link 411 and an active state is given, in which the predefinable primary detection threshold corresponds to a primary current l1 of the order of magnitude 100A.

It is additionally noted that "comprising" and "having" do not exclude further elements or steps and "a" or "an" does not exclude a plurality. It is further noted that features or steps which have been described with reference to one of the above embodiments may also be used in combination with further features or steps of further embodiments described above. Reference signs in the claims shall not be construed as limiting.

Claims

1. A secondary loop device (104') having:

-a secondary coil (L2) for transmitting and/or receiving magnetic energy of a magnetic field (106) and for converting said magnetic energy into electrical energy;

-an energy transfer device (405), the energy transfer device (405) being adapted to transfer the electrical energy;

secondary side detection means (409, 407);

a terminal switching device (301);

wherein,

-generating the magnetic field (106) by a primary coil (L1) of a primary loop arrangement (105');

-the energy transfer device (405) has an input for coupling the secondary coil (L2);

-the energy transfer device (405) has an output for providing the electrical energy as a voltage and/or current;

the secondary-side detection device (409, 407) is connected to the input and/or the output of the energy transmission device in order to detect an excess pressure at the input and/or the output of the energy transmission device; and

the secondary-side detection device (409, 407) is provided to influence the magnetic field (106) in the secondary coil (L2) by means of the terminal switching device (301) when the overvoltage at the input and/or output of the energy transmission device (405) is detected, in such a way that a current and/or voltage jump is caused in the primary coil (L1).

2. The secondary circuit arrangement (104') as claimed in claim 1, wherein the secondary-side detection device (409, 407) for detecting the excess pressure has a secondary-side comparator (409).

3. The secondary loop arrangement (104 ') as claimed in claim 2, wherein the secondary loop arrangement (104') further has: a secondary side control device (407); wherein the secondary-side control device (407) is provided for presetting a boundary value (502) of the secondary-side comparator.

4. The secondary circuit arrangement (104') as claimed in any of claims 1 to 3, wherein the terminal switching arrangement (301) is provided for reacting, upon detection of the excess pressure at the input and/or output of the energy transmission device, with at least one protective measure selected from the group consisting of:

short-circuiting the input of the energy transfer device (405);

-short-circuiting the output of the energy transfer device (405);

detuning the energy transfer device (405); and

-isolating the tank circuit (203) formed by the secondary coil (L2).

5. The secondary loop arrangement (104 ') according to any of claims 1 to 4, wherein the secondary loop arrangement (104') further has:

a secondary-side communication device;

wherein the secondary side communication means are provided for establishing a communication channel (101) with a primary loop assembly (105').

6. A primary loop arrangement (105') having:

an energy generating device (401) for providing electrical energy and a primary coil (L1) for converting the electrical energy into magnetic energy;

primary side detection means (408, 406);

wherein,

the energy generating device (401) is connected to a primary coil (L2);

-the primary coil (L2) is arranged for sending and/or receiving the magnetic energy;

-the primary side detection means (408, 406) are connected to the primary coil (L1); and is

The primary-side detection device (408, 406) is also provided for detecting a current jump in the primary coil (L1) and switching off the energy generating device (401) when the current jump is detected.

7. The primary circuit arrangement (105') as claimed in claim 6, wherein the primary-side detection device (408, 406) for detecting the current jump has a primary-side comparator (408).

8. The primary loop arrangement (105 ') according to claim 7, wherein the primary loop arrangement (105') further has: a primary-side control device (406);

wherein the primary-side control device (406) is provided for presetting the limit values (408a ', 408 b') of the primary-side comparator (408).

9. The primary loop arrangement (105 ') according to any one of claims 6 to 8, wherein the primary loop arrangement (105') further has: a primary-side communication device;

wherein the primary side communication means are arranged for establishing a communication channel (101) with a secondary loop assembly (104').

10. A system (100) for energy transfer, having:

-a vehicle mat module arrangement (104), the vehicle mat module arrangement (104) having a secondary circuit arrangement (104') according to any one of claims 1 to 5;

-a floor mat module arrangement (105), the floor mat module arrangement (105) having a primary circuit arrangement (105') according to any one of claims 6 to 9;

wherein the secondary loop arrangement (104 ') and the primary loop arrangement (105') are coupled by a magnetic field (106).

11. A method for testing a secondary loop arrangement (104') according to any one of claims 1 to 5, the method comprising:

coupling the secondary loop arrangement (104 ') with the primary loop arrangement (105') according to any one of claims 6 to 9 by means of a magnetic field;

presetting energy to be transmitted in a power presetting mode;

-triggering the terminal switching device by lowering a detection threshold (502) for identifying an overpressure in a secondary detection device (407, 409);

evaluating a current jump in the primary loop arrangement (105').

12. A method for testing a primary loop arrangement (105') according to any one of claims 6 to 9, the method comprising:

identifying a coupling to a secondary loop device (104') according to any one of claims 1 to 5;

simulating a current jump and/or a voltage jump by lowering a detection threshold (408a ', 408 b') for identifying a current jump and/or a voltage jump in the primary detection device (408, 406);

evaluating the response of the primary detection device.